if you notice his tight range on his button it makes sense that he would have hands that want to continue playing the turn, i would expect him to call pocket pairs on this flop but to fold out pocket pairs you only need to bet half pot on the turn.

i think perhaps calling and then letting him check back the flop before you bet turn and river can be a better choice since he has a tight range for button and you dont want to put in money while behind. KQs is barely ahead of his range.